Paris Hilton has devised a technique to find out how sincere her friends are, she tests their opinions on her outfits. The socialite-turned-pop star fears too many of her pals are backstabbing and only interested in selling her out to the press - so she has put together a cunning plan. Hilton explains, "I'll pick out two outfits, one which is disgusting and one nice and I'll ask my 'friend' what they think. "If they go for the revolting one, I cut them out of my life."